1. Field of the Invention
This invention pertains to tracking and alarm systems in general and more particularly to a method and apparatus for activating a vehicle's alarm in addition to reporting the vehicle's location when called from a remote location.
2. General Background
Many devices exist for tracking and locating vehicles. Some such systems simply track an individual vehicle using the global positioning system (GPS). Others are more elaborate and supply tracking and alarm services to a whole fleet of vehicles. Some of these devices are as follows.
U.S. Pat. No. 5,223,844 issued to Mansell, et al., pertains to a vehicle tracking and security system for a fleet of vehicles that sends an immediate response in case of theft, accident, breakdown, or other emergency. It also permits the driver to contact the central control center via a keypad or other interface device when needed.
U.S. Pat. No. 5,043,736 issued to Darnell, et al., pertains to a portable locating unit that is also useful as a cellular phone. The hand-held receiver sends positioning data via a cellular telephone network. The location of the object can then be determined at a remote base station location via the signals received.
U.S. Pat. No. 5,235,633 issued to Dennison, et al., pertains to cellular telephone tracking system that can monitor a plurality of vehicles from a single base unit. The signals from the various vehicles are sent based upon their geographic location rather than based upon their strength. The location of the vehicle is determined via the global positioning system which is then relayed to the base unit.
U.S. Pat. No. 4,891,650 issued to Sheffer discloses a system that can determine the location of selected vehicles. In accordance with Sheffer '650, an alarm signal is generated from a particular vehicle and received by a plurality of fixed cellular sites. Each cellular site then generates a signal dependent upon the strength of the alarm signal received. The output signal from each of the various sites is then received by a main signal detecting apparatus which, based upon the output signal strength, ascertains where the vehicle generating the alarm is located.
U.S. Pat. No. 5,225,843 issued to Thompson pertains to a communication system that synchronously communicates with a variety of individual units. The range of this communication system can be extended by allowing for the transmission time based on position information received form a global positioning system.
U.S. Pat. No. 5,032,845 issued to Velasco pertains to locating a specific vehicle by incorporating a transmitter in the vehicle Which generates a signal at a certain frequency and at certain timed intervals. This signal is eventually received by a central master station that ascertains the vehicle's position.
U.S. Pat. No. 5,111,209 issued to Toriyama pertains to a satellite-based locating system for determining the location of a mobile station. The mobile station sends a one-line transmission signal through one satellite to the fixed station while the fixed station sends a two-line signal through two satellites to the mobile station. As a result, the construction of the transmission system in the mobile station can be very simple since it need only generate a single transmission signal.
While all of the above are suitable for their intended purpose, it is a purpose of this invention to provide a vehicle module that incorporates a cellular telephone, a GPS receiver card and a microcontroller voice synthesizer card. Consequently, it is a purpose of this invention to integrate the cellular telephone and the GPS receiver card so that during operation, the module's cellular telephone can be called by any remote telephone. Another object of this invention is to permit the vehicle's microcontroller voice synthesizer card to convert GPS information coordinates to DTMF signals or to a voice synthesized signal in any language. Since this device responds with vocalized position information no unique base station is required. Still another feature of this invention is to permit the caller from the remote telephone to receive this voice synthesized signal providing the exact location of the vehicle as well as the vehicle's speed. Yet another object of this invention is to permit the caller from the remote telephone to activate an alarm system within the vehicle from this remote location. A further object of this invention is to enable the module to automatically call a specific telephone number (or a sequence of telephone numbers) upon the occurrence of an accident, breakdown, or other event. Yet another object of this invention is to permit the vehicle's user to operate the cellular telephone in the normal fashion as a receiver/transmitter. Still another object of this invention is to enable the module to receive and transmit data to/from a computer via the cellular telephone network. These and other objects and advantages of this invention will become obvious upon further investigation.